1. A method for providing a low-power wide area network, LPWAN, by transmitting and receiving signals between a central node and a plurality of peripheral nodes, using a spread-spectrum radio modulation, the method including the steps of:predefining a plurality of radio configuration levels by selecting a subset of radio physical layer configurations of all possible radio physical layer configurations, wherein said radio configuration levels are ordered from lower sensitivity processing gain to higher sensitivity processing gain;
assigning a different channel or a different subset of channels for each peripheral node to communicate with the central node; and
communicating using a periodic time slot comprising a plurality of time windows, each said time window being reserved for one respective peripheral node,
wherein each said time window is reserved for the central node to poll the respective peripheral node and for the respective peripheral node to respond to the central node polling, using the assigned channel or channels to the respective peripheral node, using a radio configuration level selected from the predefined plurality of radio configuration levels.